(i) Technical Field
The present invention relates to a developing device and an image forming apparatus that have a function to detect the state of developer.
(ii) Related Art
Image forming apparatuses are, for example, apparatuses, which form an image on a recording medium, such as paper, with toner, such as a copying machine, a facsimile machine, a printer apparatus, and a composite device having these functions together.
In such image forming apparatuses, a developer obtained by mixing a carrier, a charging accelerator, and the like in the toner is used. In a developing device provided in the image forming apparatuses, the toner is made to adhere to a developing roller from the developer contained in the container, the toner is carried onto a photoconductor by the rotation of the developing roller, and an electrostatic latent image formed on the photoconductor is developed with toner.
In such a developing device, it is known that, if deterioration, shortage, or the like of the toner occurs, the flowability of the developer may decline, and thus, a development defect may be caused.